Envelope emptying and contents stacking machine



Sept. 1, 1964 s. v. VOELKER' ENVELOPE EMPTYING AND CONTENTS STACKING MACHINE Filed Aug. 50, 1961 44/ INVHVTOR.

SAXTON V. VOELKER. BY

ATTORNEYS United States Patent 3,146,902 ENVELQPE EMPTYING AND CONTENTS STACKING MACHINE Saxton V. Voelker, 2110 Country Club Drive, Grosse Pointe Woods, Mich. Filed Aug. 30, 1961, Ser. No. 135,003 8 Claims. (Cl. 214-307) This invention relates to office machines and, in particular, to envelope contents removing and assembling machines.

Hitherto, oiiices receiving large quantities of mail have been frequently faced with the problem of identifying the contents of an envelope after the contents have been removed from the envelope and the sender has neglected to place any identification of himself or of the source of the contents upon the contents themselves, even though he may have placed this on the envelope. Large ofiices are equipped with envelope opening machines and envelope emptying machines have hitherto been provided, but the contents of the envelopes and the envelopes themselves have been separated from one another during the opening and emptying procedure, with the result that an envelope could not thereafter be mated with its contents. This was particularly unfortunate where the envelope contained a check for a payment which cannot be identified. The present invention provides a machine which, after the envelopes have been slit along one edge or two opposite edges in a conventional slitting machine, preferably along the longitudinal edge or edges, removes and assembles or stacks the contents and the envelopes which contain them in a pile consisting alternately of the contents and the particular envelope in which the contents were mailed.

Accordingly, one object of this invention is to provide an envelope contents removing and assembling machine which will automatically remove the contents of envelopes containing letters and assemble them alternately with their respective empty envelopes at high speed so that the contents of each particular envelope are immedi ately followed by the empty envelope itself from which the contents have been removed, whereby the source of the contents can be identified by the return address or other identifying matter upon the envelope even if the sender has neglected to place an identifying inscription upon the contents of the envelope.

Another object is to provide an envelope contents removing and assembling machine of the foregoing character wherein the envelope, after being edge-slit, is subjected to distension of its opposite sides to cause the contents to drop out through the opening provided by the slit edge, followed immediately by the dropping of the empty envelope itself into positions immediately behind its thus-removed contents, and deposited in a stack by a conveyor.

Another object is to provide an envelope contents removing and assembling machine as set forth in the object immediately preceding, wherein distension of the opposite sides of the envelope is brought about by vacuum or suction-operated devices which are automatically rendered inoperative by being opened to atmospheric pressure in order to release the envelope sides and permit the envelopes to drop, preferably by gravity, into a conveyor which deposits the contents and their respective envelopes alternately in a stack.

Another object is to provide an envelope contents removing and assembling machine of the foregoing character wherein the formation and removal of the vacuum from the suction devices is effected in timed relationship with the result that suflicient time is given for the envelope contents to fall out of the envelope while its opposite 3,146,902 Patented Sept. 1., 1964 ice sides are being held apart in a distended condition by the vacuum devices, immediately after which the vacuum is removed from these devices to release the envelope sides and permit the envelope to drop down freely, preferably under the influence of gravity, with or without assistance by other means, such as an air blast.

The drawing shows a diagrammatic representation of an envelope contents removing and assembling machine, according to one form of the invention.

Referring to .the drawing in detail, there is shown therein an envelope contents removing and assembling machine, generally designated 10, according to one form of the invention, as including an envelope feeder, generally designated 12, a feeding conveyor, generally designated 14, an envelope distender, generally designated 16, a removing and stacking conveyor, generally designated 18, and an envelope contents and envelope receiver, generally designated 19. The envelope feeder 12, it will be understood, handles the envelopes after they have been slit along one of their edges and preferably along both of their opposite edges by a conventional envelope slitting machine. Such machines are well known to those skilled in the oflice machine art, are available on the open market and hence require no description. The slitting of the envelopes along both of their opposite edges is preferred because it causes them to be distended more easily than if they are slit along only one edge, and is a further safeguard against contents of the envelopes sticking in or adhering to the interior walls of the envelopes. The slitting of the envelopes along their opposite edges is accomplished merely by running them through the slitting machine a second time after they have been slit along one edge.

The individual envelopes E thus slit along one or both edges, but with their contents still inside them, are placed in a stack S in a vertical receptacle 20, with one of their slit edges facing the inlet 22 of the feeding conveyor 14. The envelope feeder 12, in addition to the receptacle 20 includes a vertically-movable supporting plate 24 which is urged upwardly by a helical compression spring 26 resting upon the bottom 28 of the receptacle 20. The receptacle 20 and its contents are in turn supported by a supporting structure 30 including bottom and side walls 32 and 34 bolted or otherwise secured to the side wall 36 of the machine housing 38. The latter includes a top Wall 40, a vertical rear wall 42 and a bottom wall 44, serving as a base. The support 24 and spring 26 are so constructed and arranged that the spring 26 forces the stack S of slit envelopes E upward so that the topmost envelope E of the stack S is always at a level opposite the entrance opening 22 of the feeding conveyor 14. In that position, it is at a level convenient for engagement by a vacuum cup gripper 46 connected by a flexible hose 48 to a branch vacuum pipe line 50 containing a shutoff valve 52 and leading to a main vacuum pipe line 54 terminating at a vacuum pump 56, the input shaft 58 of which is coupled to and driven by the armature shaft 60 of an electric motor 62. The motor 62 and vacuum pump 56 are mounted upon a base 64 which in turn is bolted or otherwise secured to the housing bottom wall 44.

The vacuum cup envelope gripper 46 is pivotally connected to one end of a link 66 which in turn is pivotally connected to an oscillating or swinging arm 68 caused to swing to and fro between the solid line and dotted line positions in the upper left-hand corner of the drawing by being connected to a shaft 70 of an oscillating device 72. The latter depends from and is driven by a reduction gear set 74 which in turn is coupled as at the shaft coupling 76 to an electric driving motor 78. As a consequence, the vacuum cup envelope gripper 46 is shifted to and fro in timed relationship, gripping each envelope E momentarily and moving it off the top of the pile or stack S into the inlet 22 of the feeding conveyor 14. Here it is grasped by the upper and lower endless feeding conveyor belts 86 and 32 of the feeding conveyor 14 and thereby pulled out of the grasp of the vacuum cup gripper 46. The action of the conveyor 14 may be optionally assisted by equipping the vacuum valve 52 with a timer to operate it in timed relationship with the reciprocation of the gripper 46 so as to apply the vacuum thereto when the gripper 46 is in its rearward or dotted line position and to break the vacuum by admitting air thereto when the gripper 46 is in its forward or solid line position.

The conveyor belts 80 and 82 of the feeding conveyor 40 are supported upon idler pulleys or rolls 84 with additional idler pulleys or rolls 86 resiliently mounted as at 86 to press them together into running contact with one another inwardly of their converging entrance or inlet 22 and geared together or otherwise drivingly synchronized with one another as at 90, one of the intermeshing gears 90 being in turn driven by a belt or sprocket chain 92 from a pulley or sprocket 94 mounted upon the output shaft 26 of the speed reducing gearset 98 of an electric conveyor driving motor 100. The shaft 96 also carries a second sprocket concealed behind and similar to the sprocket 94 for driving a removing conveyor sprocket chain 102 which in turn drives one of a pair of intermeshing gears 1114 which thereby drive the upper and lower endless removing conveyor belts 106 and 106. The driven sprockets of the driving belts or sprocket chains 92 and 102 are concealed behind their respective gears 99 and 104. One of each pair of pulleys or rolls 110 and 112 at the discharge point of each of the feeding and removing conveyors 14 and 18 is resiliently mounted as at 114 and 116 respectively, adjacent its respective driven gear 99 or 104. Similarly, centain of the pulleys or rollers 118 which support the conveyor belts 166 and 108 are solidly mounted while other such pulleys 120 are resiliently mounted as at 122 to press the belts 106 and 108 into running contact with one another.

The envelope distender 16 is shown diagrammatically as including a pair of laterally-spaced approximately vertical parallel plates forming opposite side walls or gates 124 and 126, the gate or side wall 126 being optionally movable laterally, as indicated by the dotted lines to the right thereof in the drawing. Each of the side walls or gates 124 and 126 is equipped with a suction or vacuum applicator 128 or 130 respectively, such as -a suction cup opening into the space 132. The suction cup 128 is connected by a branch vacuum line 134 to the main suction line 54, to which the suction applicator 130 is connected by a flexible pipe or hose 136. The space 132 between the side walls or gates 124 and 126 may be closed in, if desired, by parallel plates forming opposite end walls at the opposite edges of the side walls 124 and 126 to form a chute with one optionally movable wall 126, these closure plates or opposite end walls being omitted for clearness of disclosure of the side walls 124 and 126, which would otherwise be concealed by them.

In order to alternately apply suction to or remove suction from the suction or vacuum applicators 128 and 130, the main suction or vacuum pipe 54 is provided with an electromagnetically-operated valve 138 which in turn is connected by an energization line 140 to a control switch 142 which in turn is connected by a line 144 to a source of electrical control current (not shown) which supplies electric current to the electro-magnetically-operated valve 138 through the line 146.

The switch 142 has an operating member 148 which in turn is actuated by a timing cam 150 rotatably mounted upon a rotary shaft 152. The rotary shaft 152 constitutes the output shaft of a reduction gear set 154 which in turn is coupled as at 156 to an electric driving motor 158. It is preferred that the motor 78 which operates the envelope feeder 12 and the motor 158 which operates the timing cam 150 shall be synchronous motors in order that their operations shall be accurately timed and maintained in precise operating relationship with one another.

The rotary shaft 152 also operates a swinging gate 160 which opens and closes the lower end of the space 132 between the fixed and movable suction plates 124 and 126. \Vhen the plate 126 is laterally movable, it is also preferably operated in timed relationship with the gate 160 and preferably also from the synchronous motor 153 and reduction gear set 154.

The contents C and the empty envelopes E from which they have been removed fall into the receiver 19 which may be in the form of a basket, secured to and held by a bracket or fixture 162 which in turn is bolted or otherwise secured to the housing floor or bottom plate 44. The feeding conveyor 14 has an outlet 164 immediately above the space 132 between the plates 124 and 126, whereas the removing conveyor 18 has a converging inlet 166 below the swinging gate 160 and an outlet 168 immediately beyond the pulleys 112.

In the operation of the invention, let it be assumed that the filled envelopes E have been passed through a conventional edge slitting machine, preferably along both of two opposite edges, for reasons stated above, and that a stack S of such mail has been placed, after edge-slitting, upon the resilient support 24 within the feeder receptacle 20, with the slit open edges facing the entrance 22 of the conveyor 14. The operator then starts the motors 62, 78, 1110 and 158 operating the various units of the apparatus 10, and causing the vacuum pump 56 to establish a suction in the main pipe 54 and branch pipes 50, 134, 136 and 43. The operation of the motor 78 of the feeder 12 causes the suction cup 46 to move back and forth, first gripping the upper surface of an envelope E in its dotted line position and moving the envelope E off the top of the stack S to the solid line position where the envelope E has entered the converging entrance between the upper and lower belts and 82 of the feeding conveyor 14. At the same time, if the vacuum valve 52 is operated by a timer, it shifts to break the vacuum in the vacuum cup 46 in its forward or solid line position, so as to further facilitate release of the envelope E, provided the momentum of the envelope E and its contents is not suficient to do so, in cooperation with the frictional drag exerted thereon by the belt 80 or 82.

The released envelope E is thus ejected into the entrance 22 of the feeding conveyor 14 and is carried by the belts 80 and 82 of the latter downward to its outlet 164 where it drops the envelope and its contents into the space 132 between the parallel plates 124 and 126. At this instant, the timing cam 15%) operates the vacuum valve 138 to apply suction to the branch pipes 134 and 13-6 and suction applicators 128 and 1311, resulting in a powerful suction force being applied to the opposite sides of the envelope E which at this time has its slit opening in one edge downward or, if both opposite edges have been slit, it has openings at both the upper and lower edges thus presented.

In either case, the suction exerted upon the opposite walls of the envelope pulls these outward away from one another, spreading these edge openings apart. As a result, the contents C within the envelope E drop downward therefrom under the force of gravity, falling upon the gate 160. The continued rotation of the timing cam 152 opens the gate 161] and releases the contents C to drop downward into the inlet or entrance 166 of the removing conveyor 18.

. Immediately thereafter the timing cam 152 operates the switch 142 to break the vacuum in the suction applicators 128 and 130, releasing the now-empty envelope to drop into the inlet 166 of the removing conveyor 18, which by this time has carried the contents downward between the upper and lower belts 106 and 108. If the envelope distender 16 is equipped with a movable plate or side wall 126, the latter at the same time moves to its dotted line position to facilitate dropping the empty envelope. It is preferred, however, from the standpoint of mechanical simplicity, to operate the envelope distender 16 with both side walls or plates 124 and 126 fixed. In the manner thus described, the envelopes E are successively emptied of their contents C and the empty envelopes E follow their respective contents C through the removing conveyor 18 into a stack S within the receiver 19, with the contents C alternating in arrangement with their respective envelopes E. After a sufficiently high stack S has been accumulated in this manner, the operator removes the stack S and clerks then examine the mail, knowing that in each instance the contents are followed immediately by the empty envelope E in which they arrived. In this way, it is a simple task to identify any contents C as to their source, provided such identifying indicia or inscriptions are present upon the accompanying envelope E.

It will be understood that in order to facilitate feeding of stacks of different sizes of envelopes containing mail, diiferent sizes of supporting plates 24 and receptacles 20 may be used, the stroke of the vacuum cup gripper 46 being adjusted so as to avoid collision with the rear wall of the receptacle 20 during such reciprocation. In lieu of changing the size of the upper receptacle 20 and supporting plate 24, a vertical envelope sizing plate may be adjustably mounted upon the support 24, and the stroke of the vacuum cup gripper 46 likewise adjusted to avoid collision therewith. It will also be understood that the lower receptacle 19 may be provided with a tilted bottom disposed at approximately the angle of tilt of the envelope E, in order to facilitate the piling up of the emptied envelopes and their respective contents removed therefrom.

It will also be understood that the machine is preferably grounded in some satisfactory and well-known manner, such as to a water pipe, in order to carry away any static electricity which may be generated during the operation of the machine and which might otherwise interfere with the smooth feeding and conveying of the envelopes and contents.

What I claim is:

1. A machine for emptying and alternately stacking the contents and emptied envelopes of edge-opened envelope mail, comprising an envelope distender having laterallyspaced generally-vertical opposite side walls defining a generally-vertical passageway therebetween with an upper inlet and a lower outlet, said distender having laterallyspaced suction applicators in said opposite side walls adapted to pull apart the opposite sides of the edge-opened envelopes passing through said passageway, means for alternately applying and terminating suction intermittently and momentarily to said applicators and adapted to momentarily distend the opened envelopes So as to drop the contents therefrom by gravity into said outlet and imme diately thereafter to drop the envelopes into said outlet in alternating succession, and a stacking conveyor disposed below said outlet of said passageway and adapted to remove and stack in alternate succession the emptied envelope contents and their respective envelopes previously containing and now emptied of such contents.

2. An envelope emptying and contents stacking machine, according to claim 1, wherein said machine also includes a filled envelope feeding conveyor having an entrance and an exit positioned respectively to receive and discharge such edge-opened filled envelopes containing such contents into the inlet of said passageway.

3. An envelope emptying and contents stacking machine, according to claim 2, wherein said feeding conveyor includes a pair of endless flexible conveying elements having portions of their courses disposed adjacent one another in gripping transporting relationship with a filled envelope passing therebetween.

4. An envelope emptying and contents stacking machine, according to claim 1, wherein said suction-applying means includes a vacuum control valve and a timing device operatively connected thereto.

5. An envelope emptying and contents stacking machine, according to claim 4, wherein said timing device includes a timing cam and wherein said suction control valve includes an electric circuit containing an electromagnetic operator operatively connected to said valve and a control switch actuated by said timing cam.

6. An envelope emptying and contents stacking machine, according to claim 2, wherein a common prime mover is drivingly connected to said filled envelope feeding conveyor and to said stacking conveyor.

7. A machine for emptying and stacking the contents and emptied envelopes of edge-opened envelope mail, comprising an envelope distender having laterally-spaced generallyvertical opposite side walls defining a generally-vercal passageway therebetween with an upper inlet and a lower outlet,

said distender having laterally-spaced suction applicators in said opposite side walls adapted to pull apart the opposite sides of the envelopes passing through said passageway,

means for applying suction intermittently and momentarily to said applicators and adapted to momentarily distend the opened envelopes and drop the contents therefrom by gravity,

a stacking conveyor disposed below said outlet of said passageway and adapted to remove and stack in alternate succession the emptied envelope contents and the envelopes emptied of such contents,

a gate disposed adjacent the outlet of said passageway,

and means for opening and closing said gate in timed relationship with said suction-applying means.

8. A machine for emptying and stacking the contents and emptied envelopes of edge-opened envelope mail, comprising an envelope distender having laterally-spaced generallyvertical opposite side walls defining a generally-vertical passageway therebetween with an upper inlet and a lower outlet,

said distender having laterally-spaced suction applicators in said opposite side walls adapted to pull apart the opposite sides of the envelopes passing through said passageway,

means for applying suction intermittently and momentarily to said applicators and adapted to momentarily distend the opened envelopes and drop the contents therefrom by gravity,

a stacking conveyor disposed below said outlet of said passageway and adapted to remove and stack in alternate succession the emptied envelope contents and the envelopes emptied of such contents,

one of said opposite side walls being mounted in said distender for movement toward and away from the other side wall,

and means for moving said movable side wall in timed relationship with said other side wall.

References Cited in the file of this patent UNITED STATES PATENTS 1,361,791 Carroll Dec. 7, 1920 1,517,255 Scholin Dec. 2, 1924 1,742,863 Jurgens Jan. 7, 1930 2,097,587 Dearing Nov. 2, 1937 2,661,948 Montgomery Dec. 8, 1953 2,806,614 Butz Sept. 17, 1957 3,016,240 Twitchell et al J an. 9, 1962 

7. A MACHINE FOR EMPTYING AND STACKING THE CONTENTS AND EMPTIED ENVELOPES OF EDGE-OPENED ENVELOPE MAIL, COMPRISING AN ENVELOPE DISTENDER HAVING LATERALLY-SPACED GENERALLYVERTICAL OPPOSITE SIDE WALLS DEFINING A GENERALLY-VERCAL PASSAGEWAY THEREBETWEEN WITH AN UPPER INLET AND A LOWER OUTLET, SAID DISTENDER HAVING LATERALLY-SPACED SUCTION APPLICATORS IN SAID OPPOSITE SIDE WALLS ADAPTED TO PULL APART THE OPPOSITE SIDES OF THE ENVELOPES PASSING THROUGH SAID PASSAGEWAY, MEANS FOR APPLYING SUCTION INTERMITTENTLY AND MOMENTARILY TO SAID APPLICATORS AND ADAPTED TO MOMENTARILY DISTEND THE OPENED ENVELOPES AND DROP THE CONTENTS THEREFROM BY GRAVITY, A STACKING CONVEYOR DISPOSED BELOW SAID OUTLET OF SAID PASSAGEWAY AND ADAPTED TO REMOVE AND STACK IN ALTERNATE SUCCESSION THE EMPTIED ENVELOPE CONTENTS AND THE ENVELOPES EMPTIED OF SUCH CONTENTS, A GATE DISPOSED ADJACENT THE OUTLET OF SAID PASSAGEWAY, AND MEANS FOR OPENING AND CLOSING SAID GATE IN TIMED RELATIONSHIP WITH SAID SUCTION-APPLYING MEANS. 